Transfusion of leukocyte-containing blood or erythrocyte concentration preparations may cause side effects such as headache, vomiting, chills, fever, viral infection, and allogeneic antigen sensitization. To prevent these side-effects, it is necessary to remove leukocytes present in blood of subjects who receive a transfusion.
Methods of removing leukocytes from blood include a centrifugation method which separates leukocytes by rotating blood at a high rate, a filter method which separates leukocytes by allowing blood to pass through a filter to adsorb leukocytes on the filter, and a dextran method which includes adding dextran to blood, stirring the mixture and then removing a separated leukocyte layer by suction. Thereamong, the filter method which exhibits excellent leukocyte separation performance, is easy to handle and is inexpensive is widely used.
Such a blood filter should satisfy a variety of requirements. First, the blood filter should treat a large amount of blood within a short time to prevent blood coagulation. Second, the blood filter should have a high leukocyte removal rate to prevent the aforementioned side-effects. Third, the blood filter should allow other beneficial ingredients in blood, for example, erythrocytes, to pass therethrough without causing damage to the ingredients.
In Korean Patent No. 1441165, the present applicant disclosed a blood filter which has an increased blood throughput per unit time as well as improved leukocyte elimination performance and erythrocyte recovery rates by imparting excellent blood affinity to a melt-blown non-woven fabric.
However, the melt-blown non-woven fabric, which is a porous material, has a low pore size uniformity. For this reason, a plurality of porous materials need to be laminated to improve leukocyte elimination performance. As a result, there are limitations on increasing blood throughput per unit time, improving erythrocyte recovery rates and reducing erythrocyte damage rates.